Yeah, upgrades are already in as is. But there's no shop to buy them - it's just a straight-out upgrade to your time, ammo, shot power, etc.
Thanks for playing either way!
mana regen needs to be fixed. its super high when under 100, making certain skills (whirpool) the only really viable ones. It's possible to win with higher level skills, but its very inefficient timewise
To get free missiles: Replay the tutorial 'blow up buildings' mission using only your machinegun. Collect the missiles when the buildings explode and use them in your next mission!
If you get the life berry eat it. The dire warnings do not mean anything, and it keeps you from falling down during the final stretch for the good ending.
We're fixing that bug right now, many apologies!